A probe core includes a frame, a wire guide connected to the frame, a probe tile, and a plurality of probe wires supported by the wire guide and probe tile. Each probe wire includes an end configured to probe a device, such as a semiconductor wafer. Each probe wire includes a signal transmitting portion and a guard portion. The probe core further includes a lock mechanism supported by the frame. The lock mechanism is configured to allow the probe core to be connected and disconnected to another test equipment or component, such as a circuit board. As one example, the probe core is configured to connect and disconnect from the test equipment or component in a rotatable lock and unlock operation or twist lock/unlock operation, where the frame is rotated relative to remainder of the core to lock/unlock the probe core.